There is an increasing use of LEDs as individual lamps or in luminaires, and which can perform additional functions beyond simple on-off control. Perhaps the most basic function is a dimming function.
Traditional incandescent light bulbs make use of phase-cut dimming approaches, and phase cut dimmer switches are used for this purpose. They may operate according to a leading edge phase cut approach or a trailing edge phase cut approach.
Universal dimmers are very popular among electrical installers. The main reason for this is that they are suitable for inductive, resistive and capacitive lighting loads. This makes life easy for the technician, since the dimmer adapts its operating mode (in particular leading or trailing edge) automatically to the load it is connected to. The installer only has to have one dimmer type in stock.
Lamps and luminaires with wireless control functions, using an on-board radio modem, are becoming more popular, so that there is a trend towards wireless controllable lamps.
The wireless communication usually takes place between the lighting load (e.g. lamp) and a bridge, often known as a hub. The hub is preferably provided as a two-wire device to fit existing electrical installations so that it can be provided as a retrofit solution. The hub is then connected in series with the load, and it has to be powered in order to operate.
However, known universal dimmers cannot operate these wireless lighting loads. Furthermore, available wireless dimmers are not suitable for universal loads. A wireless dimmer in the context of this application is one which is controllable via wireless communication (e.g. ZLL, WiFi or Bluetooth), while the interface to the lighting load is still a phase-cut signal.
Typically a wall switch, such as a dimmer switch, lasts for 20 years and even when it initially will be used with phase-cut dimmable lighting loads, it would be desirable if it could also be used for wireless connected lighting loads.
There is therefore a need for a lighting apparatus control switch that can cover all state of the art technologies. This would then enable ease of installation and avoid confusion at the customer side. The lighting apparatus control switch should be a two-wire unit so that it can replace existing wall switches (where no neutral wire is present) without requiring wiring alterations.
Powering of such a unit can be implemented with batteries or other energy storage or energy harvesting technologies. However, a more user-friendly and maintenance free solution is to power the lighting apparatus control switch directly via the mains. There is therefore a further need for a universal lighting apparatus control switch which can replace existing two-wire wall switches.
GB 2444527 A1 discloses a device for replacing conventional wall mounted light switches in situ comprises a dimmer and an occupancy sensor. The device can vary the power output to a lighting device in response to a manually operable control and also signals generated by the occupancy sensor. The occupancy sensor may be a PIR (passive infrared) type detector. A light sensor and a timer may also be provided. The device may also have two operating regimes, one for incandescent lamps and one for non-incandescent lamps.
SG 186590 A1 discloses a device for controlling an output of a load, the device including: a conduction angle changing circuit; a current scanner; and a digital signal processing unit including: a preset load type acquiring module; and a continuous template matching module adapted to perform continuous template matching at a predetermined timing in an event that the acquired preset load type is a non-linear dimmable load, the continuous template matching module including: a conduction angle range determining sub-module adapted to determine a conduction angle range; a local pattern acquiring sub-module adapted to acquire a local pattern in response to changing the conduction angle within the conduction angle range; a matching submodule adapted to match the local pattern with the local pattern in a current pattern template; and an updating sub-module adapted to update a control parameter for the load in accordance with a matching result.